Homeostasis and general principles

Question 1

What are the lobes of the brain?

Answer 1

Frontal lobe
Parietal lobe
Occipital lobe
Temporal lobe

Question 2

What is the Central Nervous System comprised of?

Answer 2

Brain and Spinal cord

Question 3

What is the Peripheral Nervous System comprised of?

Answer 3

Nerve and nerve cells outside the brain and spinal cord

Question 4

What is the neuron responsible for?

Answer 4

Initiating, mediating, modulating most physiological processes in the body

Question 5

What are electrical signals carried in?

Answer 5

Nerve cells

Question 6

What is homeostasis?

Answer 6

Condition of equilibrium (balance) in the body’s internal environment due to constant interaction of the body’s many regulatory processes

Question 7

What are the normal levels within the body for PO2, PCO2, temperature, blood pressure etc?

Answer 7

PO2- 100mmHg
PCO2- 40mmHg
Blood pressure- 120/80 mmHg
Temperature- 37°C
pH- 7.4
Plasma glucose- 5.5mM

Question 8

Where is intracellular fluid?

Answer 8

Within cells

Question 9

Where is extracellular fluid?

Answer 9

Outside cells

Question 10

Where is ECF in intersitial fluid?

Answer 10

Extracellular fluid between cells of tissues

Question 11

Where is ECF in blood plasma?

Answer 11

Within blood vessels

Question 12

Where is ECF in lymph?

Answer 12

Lymphatic vessels

Question 13

Where is ECF in cerebrospinal fluid?

Answer 13

Around brain and spinal cord

Question 14

Where is ECF in synovial fluid?

Answer 14

In joints

Question 15

Where is ECF in aqueous humour and vitreous body?

Answer 15

In eye

Question 16

What causes disruption in the internal body?

Answer 16

External environment e.g. heat, O2 levels
Internal environment e.g. reduced glucose
Psychological stress

Question 17

What 2 regulating systems bring internal environment back to equilibrium?

Answer 17

Endocrine and Nervous system

Question 18

What is a stimulus?

Answer 18

A disruption that changes a controlled conditions

Question 19

What is a controlled condition?

Answer 19

A monitored variable, e.g. blood pressure, temperatures, blood glucose levels

Question 20

What is a receptor?

Answer 20

Monitors changes in controlled condition and sends input to a control centre

Question 21

What type of pathway goes from the receptor to the brain?

Answer 21

Afferent Pathway

Question 22

What is the control centre?

Answer 22

Evaluates input from receptors then generates output commands when needed

Question 23

What kind of signals are sent out from the Control centre?

Answer 23

Typically nerve impulses, hormones or other chemical signals

Question 24

What type of pathway goes from the Brain to the effectors?

Answer 24

Efferent Pathway

Question 25

What is an effector?

Answer 25

A structure that produces a response or effect that changes the controlled condition. Most organs and tissues in the body can be an effector

Question 26

What is a response?

Answer 26

Alters the controlled condition in some way, either reversing (negative feedback loop) or enhancing (positive feedback loop)

Question 27

When is homeostasis reached?

Answer 27

When controlled condition is back to normal

Question 28

What is a positive feedback loop?

Answer 28

Continually reinforces a change in a controlled condition, some event outside the system must shut it off

Question 29

What is a negative feedback loop?

Answer 29

Slows and then stops when the controlled condition returns to its normal states, regulates conditions in the body that remain stable over time